1. |
Reciprocity laws for simple algebras over function fields of number curves |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1657-1683
V.I. Guletskiǐ,
V.I. Yanchevskiǐ,
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ISSN:0092-7872
DOI:10.1080/00927870008826921
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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2. |
The automorphism group of the derived category for a weighted projective line |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1685-1700
Helmut Lenzing,
Hagen Meltzer,
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摘要:
We show that up to a translation each automorphism of the derived categoryDbXof coherent sheaves on a weighted projective line X, equiv-alently of the derived categoryDbAof finite dimensional modules over a derived canonical algebraA, is composed of tubular mutations and automorphisms of X. In the case of genus one this implies that the automorphism group is a semi-direct product of the braid group on three strands by a finite group.
ISSN:0092-7872
DOI:10.1080/00927870008826922
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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3. |
Semi-invariants of actions of multiplier hopf algebras |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1701-1716
Lydia Delvaux,
Alfons Van Daele,
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摘要:
LetAbe a multiplier Hopf algebra which acts on an algebraR. In this paper we study semi-invariants of this action. This idea has proved interesting in the case thatAis a Hopf algebra.
ISSN:0092-7872
DOI:10.1080/00927870008826923
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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4. |
Enumeration of subgroups in the fundamental groups of orientable circle bundles over surfaces |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1717-1738
Valery Liskovets,
Alexander Mednykh,
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摘要:
The aim of this paper is to count subgroups of a given index in the fundamental group of an orientableS1-bundle over a compact surface. The number of subgroups of indexnturns out to be independent of the orientability of the base surface 𝔣, closed or bordered, and is expressed as a linear combination of the numbers of surface subgroups of indicesm = n/ll∣n. For a closed base surface of characteristic χ the respective coefficients are equal tol–χm+2or vanish depending onl,nand the Euler number of theS1-bundle.
ISSN:0092-7872
DOI:10.1080/00927870008826924
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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5. |
Picard groups for graded coalgebras |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1739-1765
J. Cuadra,
J.R. García Rozas,
B. Torrecillas,
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ISSN:0092-7872
DOI:10.1080/00927870008826925
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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6. |
On the topology of a generic fibre of a polynomial function |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1767-1787
E. Artal,
I. Luengo,
A. Melle,
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摘要:
In this work we study the topologies of the fibres of some families of complex polynomial functions with isolated critical points. We consider polynomials with some transversality conditions at infinity and compute explicitly its global Milnor number μ(f). the invariant λ(f) and therefore the Euler characteristic of its generic fibre. We show that under some mild ransversality condition (transversal at infinity) the behavior offat infinity is good and the topology of the generic fibre is determined by the two homogeneous parts of higher degree offFinally we study families of polynomials, called two-term polynomials. This polynomials may have atypical values at infinity. Given such a two-term polynomialfwe characterize its atypical values by some invariants off. These polynomials are a source of interesting examples.
ISSN:0092-7872
DOI:10.1080/00927870008826926
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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7. |
Irreducible representations of finite exceptional groups of lie type containing matrices with simple spectra |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1789-1833
I.D. Suprunenko,
A.E. Zalesskii,
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摘要:
Absolutely irreducible representations of finite groups of exceptional Lie types in defining characteristic whose images contain matrices with simple spectra are determined. The term ”simple spectrum“ means that each eigenvalue has multiplicity 1. The similar question for the classical finite groups has been solved in the authors' previous paper [Comm. in Algebra 26 (1998), no 3, 863-888] where one can find general comments to the problem. For dimensions ≥ 100 all absolutely irreducible representations of finite groups of Lie type in defining characteristic containing matrices with simple spectra are tabulated.
ISSN:0092-7872
DOI:10.1080/00927870008826927
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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8. |
A triangularity result for associated varieties of highest weight modules |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1835-1843
William M. McGovern,
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摘要:
We prove a conjecture of Tanisaki in the classical case, which says roughly that the matrix of orbital varieties occurring in the associated variety of a simple highest weight module is upper triangular.
ISSN:0092-7872
DOI:10.1080/00927870008826928
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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9. |
Morphisms of double frobenius algebras. i |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1845-1860
M. Koppinen,
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摘要:
Double Frobenius algebras (or dF-algebras) were recently introduced by the author. The concept includes finite-dimensional Hopf algebras, adjacency algebras of (non-commutative) association schemes, andC-algebras (character algebras). In this paper we define certain kinds of morphisms of dF-algebras and develop their basic theory. The morphisms generalize homomorphisms of Hopf algebras and ofC-algebras.
ISSN:0092-7872
DOI:10.1080/00927870008826929
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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10. |
On the monotonicity of the hilbert function of the sally module |
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Communications in Algebra,
Volume 28,
Issue 4,
2000,
Page 1861-1866
Luisa Rodriguez Doering,
Maria Vaz Pinto,
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ISSN:0092-7872
DOI:10.1080/00927870008826930
出版商:Gordon and Breach Science Publishers Ltd.
年代:2000
数据来源: Taylor
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